On the video there is no sign of a wooden object or of Mr Magnitz being kicked.

Frank Passade, spokesman for the public prosecutor's office, had said earlier that the footage showed Mr Magnitz likely sustained his head injuries when he hit the ground, and not from being kicked on the ground.

It is clear from the video that he had his hands in his pockets seconds before the attack took place.

Image copyrightPolizei BremenImage caption
The CCTV footage appears to differ from the Bremen AfD account of the attack on the MP

The video was made public after a Bremen court ordered its release as part of an investigation into the assault.

What happened in Bremen?

Mr Magnitz, 66, had just left a new year reception in Bremen's Kunsthalle art museum when he was attacked in the city's Goetheplatz as he walked to a central car park.

Mr Magnitz said he could not remember the attack. He has since checked himself out of the hospital.

The Bremen AfD party said he had been hit over the head with a piece of wood then kicked in the head. They said two local tradesmen ran to aid Mr Magnitz as his attackers kicked him on the ground.

Police said initially that he had been hit on the head with an unknown object and suspected a politically motivated attack. After seeing the video they said no such object was used and the tradesmen had not witnessed the attack.

Joint party leader Alice Weidel had described the incident as an "assassination attempt" while local officials in Bremen blamed "incitement" from the centre-left SPD and Green parties.

AfD later changed their account of the attack as the tradesmen had not seen the attack. However, they maintained a wooden object had been used.

Mr Magnitz also conceded the attack may have been a mugging, after initially describing it as "a politically motivated assassination attempt".

AfD Bremen politician Thomas Jürgewitz told Berliner Morgenpost the party would describe the attack "a little differently" now, but said its initial communique was in line with what was known at the time.

Image copyrightTheImage caption
Mr Magnitz had just left a new year event in Bremen when he was attacked

AfD entered the national parliament (Bundestag) for the first time last year with 94 seats and now has representatives in every German state parliament.

Its anti-immigration platform has struck a chord, particularly in eastern Germany where it hopes to make gains in three state elections this year. AfD is also eyeing the May 2019 European Parliament elections.

Last week an AfD office in the eastern town of Döbeln was damaged by an explosion. No-one was hurt.

SPD leader Andrea Nahles said that AfD was a "political opponent" of Germany's tolerant society but anyone trying to fight it with violence "betrays these values and jeopardises our co-existence".